sql`SELECT table_name, constraint_name FROM information_schema.table_constraints WHERE constraint_type='FOREIGN KEY'AND table_schema='public';```这个查询将从`information_schema.table_constraints`视图中检索所有在`public`模式下定义的外部键。## 删除所有表的逻辑外键在删除逻辑外键之前,请务必备份数据库,...
PRIMARY KEY ( column_name [, ... ] ) index_parameters | EXCLUDE [ USING index_method ] ( exclude_element WITH operator [, ... ] ) index_parameters [WHERE( predicate ) ] | FOREIGN KEY ( column_name [, ... ] ) REFERENCES reftable [ ( refcolumn [, ... ] ) ] [ MATCH FULL ...
[ { UNION | INTERSECT | EXCEPT } [ ALL | DISTINCT ] select ] [ ORDER BY expression [ ASC | DESC | USING operator ] [ NULLS { FIRST | LAST } ] [, ...] ] [ LIMIT { count | ALL } ] [ OFFSET start [ ROW | ROWS ] ] [ FETCH { FIRST | NEXT } [ count ] { ROW | RO...
postgres=# \d tbl1Table"public.tbl1"Column|Type|Modifiers---+---+---id|integer|info|text|Foreign-key constraints: "tbl1_id_fkey"FOREIGNKEY (id)REFERENCEStbl(id) postgres=# \di Listofrelations Schema|Name|Type|Owner|Table---+---+---+---+---public|tbl_pkey|index|postgres|tbl (1...
SET CONSTRAINTS设置当前事务的约束检查模式。SET CONSTRAINTS { ALL | name [, ...] } { DEFERRED | IMMEDIATE }SET SESSION AUTHORIZATION为当前会话设置会话用户标识符和当前用户标识符。SET [ SESSION | LOCAL ] SESSION AUTHORIZATION username SET [ SESSION | LOCAL ] SESSION AUTHORIZATION DEFAULT RESET ...
PostgreSQL Tutorial/Getting Started/Foreign Key PostgreSQL Foreign Key Summary: in this tutorial, you will learn about the PostgreSQL foreign key and how to add foreign keys to tables using foreign key constraints. Introduction to PostgreSQL Foreign Key Constraint In PostgreSQL, a foreign key is a ...
[ LIMIT { count | ALL } ] [ OFFSET start [ ROW | ROWS ] ] [ FETCH { FIRST | NEXT } [ count ] { ROW | ROWS } ONLY ] [ FOR { UPDATE | NO KEY UPDATE | SHARE | KEY SHARE } [ OF table_name [, ...] ] [ NOWAIT | SKIP LOCKED ] [...] ] ...
Foreign-key constraints: "t_f_f1_fkey"FOREIGN KEY(f1)REFERENCES t_p(f1) Distribute By: SHARD(f1) Location Nodes: ALL DATANODES 外键使用限制 外键只是同一个节点内约束有效果,所以外键字段和对应主键字段必需都是表的分布键,否则由于数据分布于不同的节点内会导致更新失败。
Partitioned tables do not support UNIQUE, PRIMARY KEY, EXCLUDE,orFOREIGN KEY constraints; however, you can define these constraints on individual partitions. When using range partitioning, a NOT NULL constraint isaddedto each non-expression column in the partition key. ...
group中需要添加DN节点,每个group会均匀分配总共4096个shardkey。 下面演示如何创建一个default group: 1.切换为tbase用户 su tbase。 2.连接数据库:注意:是连接到cn节点(后面没特别说明,所有数据库操作都是连接到cn节点)。 3.查询当前什么数据节点(DN),这些DN节点就是上面初始化集群时建立的。 postgres=# select...